Conventionally, such a structure is known as that a suspension supports a wheel to a body such as four-wheeled vehicles, two-wheeled vehicles, and the like and absorbs a vibration caused at the time of travel. The known structure also features that a damping force of the suspension is made adjustable with electronic control.
Patent Literature 1 discloses a suspension capable of varying a damping force. The suspension is used for four-wheeled vehicles. The suspension is capable of adjusting the damping force with a solenoid valve driven by electric power. For a predetermined period even after a power switch of the vehicle is turned off, the damping force like the damping force during travel is kept to suppress the body's vibration caused by riding-on/getting-off of an occupant or by loading/unloading of a baggage.